Frustration rankles Lyme disease patients over test results

Sunday

Jun 22, 2014 at 6:00 AMJun 22, 2014 at 8:07 PM

By Beth Daley NEW ENGLAND CENTER FOR INVESTIGATIVE REPORTING

As Lyme disease becomes an increasingly challenging public health threat across the Northeast, a growing number of tests for the vexing ailment may be misdiagnosing patients when telling them that they have — or don't have — the tick-borne illness.

An exemption in federal regulations allows many labs to offer Lyme tests without proof that they accurately identify the disease, leaving anxious patients and their doctors to decide which tests to believe.

"There are desperately ill people looking for an answer. But there are so many companies using (unproven tests) … you can't trust them,'' said Andrew Onderdonk, a professor of pathology at Harvard Medical School who was diagnosed with Lyme disease in 2012 using a federally recommended test.

While the loophole in U.S. Food and Drug Administration regulations affects a wide variety of tests, it has particular significance with Lyme disease because controversy exists over its diagnosis, treatment and how long the illness can last. Thousands of sick people believe they have a chronic form of the illness that can evade antibiotics and last years, but medical establishment doctors often dismiss this idea of long-term Lyme.

Ailing patients are increasingly forced to negotiate between the parallel medical worlds of doctors who use only federally recommended Lyme tests that may not catch the disease early on and "Lyme-literate" doctors who may diagnose them with chronic Lyme, often by using these alternative tests. Most insurers do not cover these tests, which range from $100 to more than $1,000, forcing patients to swallow the cost.

Federally recommended tests identify about 300,000 new cases of Lyme each year in the United States, more than three-quarters in the Northeast. In addition, medical authorities say, many other people are diagnosed with alternative tests that may be inaccurate, leading to unnecessary, inappropriate and costly treatment.

In Massachusetts, a bill proposed for about a decade by Rep. Ted Speliotis, D-Danvers, to extend insurance coverage for Lyme patients with long-term symptoms, is in committee and Speliotis says he is "encouraged" it will go before the full Legislature.

Worcester-based Fallon Community Health Plan said Lyme and other tick-borne infections are significant problems in Central Massachusetts and said the insurer wants the best treatments available.

"We rely on the predominance of expert opinion and evidence-based guidelines from the Centers for Disease Control and the Infectious Disease Society of America to inform our coverage decisions for both lab testing and treatment guidelines for Lyme disease," said Dr. Sarika Aggarwal, executive vice president and chief medical officer.

At least seven labs in the U.S. have been denied permission to offer Lyme tests over the past decade in New York, according to state records obtained by the New England Center for Investigative Reporting. The state is the only one that performs a rigorous review of tests to ensure they identify what they claim to before they can be offered there.

A LOOPHOLE CREATES A MARKET

The federal test exemption dates back to the 1970s when the FDA began regulating diagnostic tests but exempted what was then a small group of relatively simple tests developed, manufactured and performed all in a single lab — for example, in a hospital. Many of the tests were low-risk, variations of common tests, or designed for rare diseases and could not be validated well in studies.

The exemption has since become a market incentive for companies that produce thousands of FDA-exempt diagnostic tests, from prenatal screening to identification of genetic mutations known to increase the risk of cancer.

The FDA announced its intention to regulate these tests in 2010, but has been opposed by many laboratories that argue their facilities are already well regulated and the new rules would be cost-prohibitive, take too much time and stifle innovation that can help patients. While many of these tests do go through robust and independent validation, not all do, making it challenging for doctors and the public to distinguish between the two.

Indeed, thousands of sick people rely on the unproven Lyme tests, in part, because when the results provide a diagnosis, patients then have a hope of a treatment and cure. Many say they feel better once on medication, which is further validation for them that they were diagnosed correctly.

Lyme is one of the Northeast's most insidious public health threats. Deer ticks no bigger than a poppy seed can latch onto people during outdoor activities. The parasites, while feeding on a host's blood, can transfer the Lyme bacteria and other disease-causing pathogens. Early Lyme symptoms can mimic those of the flu and, untreated, the disease can cause arthritis, among other ailments.

The CDC-recommended method is far from perfect. It can miss the disease more often than it catches it in its early stages, although its accuracy improves greatly as the disease progresses.

It can also tell people they are positive even after the disease is gone, acknowledge federal health officials. Yet despite the limitations, they say a test has not come along yet that has proven to perform better. So, they still recommend the tests in addition to a doctor's judgment based on symptoms and whether the person lives in a tick-prone area.

"What needs to be done are longitudinal studies and blinded samples from a third party with no vested interest,'' says Sam Donta, a physician and consultant at Falmouth Hospital who specializes in Lyme disease. He says the CDC test is far too strict and omits valid cases of Lyme. But he's unwilling to use tests that are not validated. "We need something unbiased."

THOUSANDS OF QUESTIONABLE TESTS

When people notice a tick bite or get sick in the summer in a Lyme-prone area, many will call their doctor. If a telltale bull's-eye rash is present, a doctor will often assume Lyme and prescribe antibiotics without testing.

But not everyone gets or notices the rash, so most mainstream doctors turn to the CDC-recommended test. The two-step process first looks for increased antibodies in the blood that react to the Lyme bacteria. But because someone can test positive and not have the disease, a second test, known as a Western blot, is performed to more accurately identify antibodies specific to the Lyme bacteria.

While the CDC has specific guidelines to interpret the results to identify Lyme, some labs interpret them far more liberally. IGeneX Inc., for example, a Palo Alto, California, lab that performs more than 20,000 Lyme tests a year, uses different interpretation criteria for the Western blot.

On its website, the lab also offers others, such as a urine test, that is not recommended by the CDC. IGeneX was rejected by New York three times for Lyme tests in the past decade for not having enough documentation to prove the tests worked. The lab did not respond to requests for comment.

Other labs use different means to test for Lyme. Advanced Laboratory Services Inc. outside Philadelphia, for example, says it can detect and grow the bacteria that cause Lyme, a method most Lyme researchers have never been able to reliably do. The lab has conducted more than 4,000 tests but now does less than 50 a week, according to officials there.

The facility has come under sustained criticism by scientists and regulators since its test went on the market in 2011. New York rejected it in 2012 because, the state concluded, there was no proof it worked, and inspectors who visited the facility uncovered "broad substandard" laboratory practices, including an employee not wearing protective gear and a lack of lab supervision.

A federal scientist last year also published a critical study about the company's methods, raising contamination concerns.

NOT ALL ALTERNATIVE TESTS ARE BAD

Of course, not all tests rejected by the state of New York are problematic, said state officials. While tests may be rejected when developers fail to prove their validity, said Michael P. Ryan, director of the Division of Laboratory Quality Certification for the New York State Department of Health, those tests can be resubmitted as better data becomes available.

Still, many doctors say they can only abide by the scientific method, which requires evidence, such as reproducible results by an independent party in peer-reviewed literature, that a test does what it says it will.

Fredric Silverblatt, a doctor who runs a Lyme clinic in southern Rhode Island, said he often sees patients who have been on antibiotics for years without tangible results and who have tested negative on CDC-recommended tests. In those cases, he questions if they really have the disease.

One way to resolve the controversy, he said, is "to better understand how the body reacts to Lyme."

With that will come clarity on how people are affected and better tests.

The New England Center for Investigative Reporting, www.necir.org, is a nonprofit news outlet based at Boston University and WGBH TV and Radio in Boston.

NECIR interns Amanda Ostini, Carl Mueller and Michael Bottari assisted with the research for this story.